The previous discussion was intended to provide a background for the heart of this text. Just as there is a legal requirement for a comprehensive plan as the basis for land use controls, so there is a theoretical requirement for comprehensive planning as the basis for sound site design. By virtue of its name, comprehensive land use planning suggests a broad approach to the process of new development or expansion of existing development within the environment on the basis of a range of considerations including economic, social and physical factors among others. It certainly implies planning within a larger context beyond the individual site.
In practice however, this may often not be the case. Steiner criticizes Lynchs site planning model (See ensuing section for an explanation of this model), stating that design is not part of the broader planning concerns, except in its response to government restrictions, nor is the site linked to its larger context (Steiner 208). Simonds acknowledges that in traditional land planning (s)ometimes the effects on the neighboring lands and waters were considered. Sometimes they were not. In our emerging environmental and land use ethic it is believed that they should and must be (Simonds 118).
In fact, comprehensive land use planning is a complementary process. An understanding of landscape at the regional scale is an essential prerequisite to smaller scale site planning and detailed landscape design... . Conversely many of the criteria for land use in regional land use planning should be based on an understanding of construction and grading techniques used in site planning (Laurie 117). The essence of this discussion is the importance of planning and design within a context rather than in a vacuum.
A. Site Planning / Design Process
Planning and design occur as a process, by which we mean that they follow a logical sequence of actions or events that must be carried out to arrive at a viable solution. It is a multi-disciplinary problem-solving operation often involving architects, landscape architects and engineers, and frequently may require input from physical scientists as well to address environmental issues. It requires a logical objectivity for some steps, but also allows room for subjective design interpretation at others.
There are several notable models from which we can draw to understand the basic components of the site planning and design process. Kevin Lynch outlines an eight-stage site planning cycle (see Fig. 1) that includes:
1. Defining the problem
2. Programming and the analysis of site and user
3. Schematic design and the preliminary cost estimate
4. Developed design and detailed costing
5. Contract documents
6. Bidding and contracting
8. Occupation and management (Lynch 11)
John Simonds outlines a six-phase planning-design process
that applies to architecture, landscape architecture, and engineering.
This process, (see Fig. 2), is organized as follows:
6. Operation (Simonds 128-129)
There are many variations on these models. They differ essentially in the breakdown of component phases and some, such as Simonds, extend the process to include preliminary contractual agreement and post-construction operations. However, most discussions of this process agree that it is not linear (including Simonds, despite its appearance) but rather loops back on itself. Knowledge of a later phase influences conduct of an earlier one, and early decisions are later reworked (Lynch 11).
Secondly, no matter how many subparts are included, most process models can be divided into three general activities: Research (Program Development, Site Inventory); Analysis (Site Analysis); Synthesis (Conceptual Design, Preliminary Design, and Site Plan/Master Plan). For this discussion, we will look at the planning and design process under this general breakdown. We will begin with the program and conclude with the site plan or master plan. We will then look at the implementation of the design in terms of construction drawings and specifications. We will conclude this segment with a look at design guidelines, which relate to the post-construction operational/management issues.
1. Research and Analysis Phases
The entire process begins with the determination of a problem to be solved. Obviously, it is land use related, frequently initiated by a client contacting a planner to design a particular facility, often for a predetermined site. Program development is a good example of the cyclical nature of the design process. We begin with the clients wishes what sort of development is he/she looking for? What are the clients expressed goals and objectives? The answers to these questions put the planner into an appropriate mindset to begin the process. But, to develop the maximum site potential he/she does not want to restrict his/her ideas only to these uses or facilities. So, we use these responses as the initial determination of a program and will return to this issue a bit later in the process.
The examples used to illustrate the first part of the design process for this text have been taken from a West Virginia University Landscape Architecture Senior Project completed by R.M. Lilly and W.S. Loll during the spring 1999 semester. The project client wished to expand and diversify the operation of a beef cattle production enterprise on a site partially undergoing surface mining activities. The initial program statement referred to the application of land management practices to multiple uses including wildlife management, outdoor recreation and natural resource utilization. This very general expression provided guidance in the first phase of the design process.
At this point in the process, the designer can use this
general goal statement plus the identification of the site to begin collecting
information relevant to the site and the surrounding area and compiling it in a
form in which it can be mapped. This data is then analyzed in terms of
its implications for development of the site for the stated purpose. These are
in fact two distinct steps, inventory or research and analysis. We first
need to identify the factors (inventory) and then analyze each factors
potential impact upon the proposed development. Most of the
considerations in this phase of site planning have economic as well as
environmental implications. The end objective relates to the efficient
establishment of the proposed development while being sensitive to the
environmental characteristics of the site and its surroundings. As Laurie
points out, inventory and analysis of a selected parcels characteristics,
as well as its relationship with adjacent land uses, will provide
determinants of form, constraints, and opportunities for the location of
buildings [and other site facilities] and the conservation of amenities
(Laurie 118). In the interest of efficiency as well as clarity we are
going to identify the major components and discuss their implications
a. Site Location The site must be placed within its proper geographical, political, and functional context. This fixes the site in relation to adjacent land uses, community transportation patterns, utility and infrastructure availability, employment, commercial, cultural and recreational centers. Each of these has a bearing on the site development potential. For example, the adjacent land use patterns will determine the appropriate land use for a proposed site based upon the comprehensive plan. The availability of roads, and in some cases mass transit may have a significant influence on if, and for what, a site is suitable in terms of access. The presence of water, sewers, and other utilities can also dictate the suitability of a site as a target for expansion. And of course the proximity to work, jobs, and schools are a factor in real estate suitability.2. Program Development
b. Existing Conditions Depending upon the size and complexity of the site, this may be one or a series of base plans or maps that delineates and evaluates the physical attributes and constraints for the parcel of land. It will cover such items as:1) Topography and Slopes Treatment of these factors requires base information in the form of contours and elevations to a degree of accuracy appropriate to the proposed development. For general planning, topographic information such as is available from U.S. Geological Survey quadrangle maps may be suitable. However, more detailed site design requires more specific elevations from aerial or field surveys. Visually, as well as functionally, the form of the landscape, its slopes and patterns are one of the most important categories to consider, no matter what the proposed land use. The topographic map provides a considerable amount of information including drainage patterns and problems, potential on-site and off-site views, erosion and sedimentation potential, as well as potential for development. There are standards that establish categories of slopes related to suitability for different uses and activities. These standards are somewhat regional. For example, the acceptable range of slopes in the mid-West is apt to be more restricted than that used in western Pennsylvania or West Virginia where steeper natural slopes are more prevalent. A typical slope breakdown might include:
0-2% - Most developable
2-8% - Easily accommodates most categories of development
8-16% - Some development restrictions; upper limits for roads and walks
16-24% - Significant restrictions to most development
24%+ - Generally restricted for development
The slope categories are also keyed to the proposed land use or types of facilities. Obviously slopes that are suitable for certain activities may be restrictive for others. (See Fig. 3).
2) Geology and Soils General information is available from U.S.Geological Survey quadrangle maps and U.S.Department of Agriculture soil surveys. More explicit information may be required from core drillings and specific soil testing. The subsurface geology is the basis for the visible landform discussed above. Other implications are the engineering characteristics such as bearing capacity that determine suitable locations for structures and other heavy elements. Conversely, shallow depth to bedrock may restrict certain construction options on the basis of cost and impact of development. Similarly, a high water table may limit or restrict some sanitary sewage options.
Closely related are the soils characteristics which are frequently a direct product of the underlying geology. The soils may be important in terms of stability, suitability for structural foundations, erosion susceptibility, surface drainage, and soil fertility to support plant growth. Again, the suitability of soils is very much dependent upon the proposed uses. A site suitable for intensive structural development may be unsuitable for recreational activities and vice-versa. (See Fig. 4)
3) Vegetation The existing vegetation patterns and types can be obtained from aerial photographs and maps. Detailed plant identification and location of specimen plants may require field study and measurement. The significance of vegetative information relates to a range of development issues. The visual character and spatial definition of a site is impacted by the amount and category of vegetation from ground cover to canopy, from new growth to mature stands of trees, etc. Vegetation can modify the climate by providing shade, protecting potential development from winter winds or by channeling summer breezes. Plant coverage enhances soil stability, provides an indication of soil conditions (e.g., wetlands) and relates to potential wildlife habitats. Therefore, a site with extensive mature vegetation would be less suitable for high-density development from the standpoint of environmental character. The presence of trees and other plants may on the other hand make a site attractive for certain kinds of housing and/or for recreation facilities. (See Fig. 5)
4) Hydrology and Drainage U.S. Geological Service quadrangle maps provide a good base of information for this analysis, supplemented with flood data from the U.S. Corps of Engineers and local flood maps. Surface hydrology is an integral part of the slopes and subsurface drainage systems. The kinds of information normally indicated and analyzed include determination of watersheds (basically a system of ridge lines and valleys or drainage patterns), duration and volume of flow, swales, streams, standing water, and flood plain definition. Susceptibility to erosion and the problem of sedimentation to off-site water flow are also problems to be noted. Generally it is advisable to avoid disturbing natural subsurface drainage patterns such as high water tables which have implications for locations of structures or excavations. (See Fig. 6)
5) Microclimate Information on general climatic factors such as seasonal temperature averages, amounts of precipitation, etc. are available locally. Microclimatic factors refer to variations to the general climate such as might be created by topography, plants and vegetation, exposure to winds, elevation above sea level, and relationships to structural elements. These factors are important to design in terms of delineating the opportunities and constraints of a particular site for development noted by Laurie (See earlier discussion). Slopes are analyzed in relation to solar orientation to determine warm and cool slopes, based on sun exposure. Shade and shadow patterns created by existing vegetation and structures are important to design in terms of potential positive or negative impacts for development. Plants may be used to ameliorate undesirable conditions by providing windbreaks, shade, etc. (See Fig.7)
6) Views A visual analysis is the most practical means of determining positive and negative on-site and off-site views. This study is useful in determining the visual character of the site itself as viewed from the outside as well as the visual impact of its surroundings upon potential on-site development. Factors to be examined include mass and space definition from natural and man-made elements, off-site views to be accentuated or screened, and on-site view opportunities or problems.
7) Existing Structures / Infrastructure The availability of essential utilities water, sanitary sewer, storm sewer, gas, electric, telephone, etc. is crucial to the potential for site development from both an economic and environmental standpoint. If utilities are available to tap into directly adjacent to a site, the costs of development may be significantly minimized. Environmentally, if storm and sanitary sewers are not available, the options for land development may be severely restricted. Available municipal facilities may be at capacity or receiving streams may be restricted to additional outflow by state and federal environmental regulations. Off-site systems such as transportation networks (vehicular, pedestrian, bicycle) may also be the determining factor in the suitability of a site for a particular land use. This relates to issues of accessibility, ranging from commuting distances to work, to convenience and safety for pedestrians, to enhancement of recreation opportunities. (See Fig. 8)
8) Legal Constraints These may include legal property boundaries, easements , rights of way; restrictive covenants, and deed restrictions. Local regulations such as zoning ordinances and subdivision regulations may impose limitations upon what a developer is allowed to do on a given site and provide procedural requirements by which development may move forward.
This information, in a totally objective format, is critical to the designer in terms of becoming familiar with the site. It then serves as the basis for developing a sense of the opportunities and constraints provided by the site for development. Thus, the next step after cataloging or mapping the above information is to analyze its implications for development. This may be done on a separate set of maps (plans) or combined with the inventory information on the same drawing.
In either case, the end product of the site analysis phase of the design process is a composite analysis map (sometimes referred to as an opportunities and constraints sheet). This is developed through an overlay process (similar to McHargs planning approach, although greatly simplified) delineating the most suitable and least suitable areas of the site for each analysis factor.
Generally, these areas will reinforce one another. That is, steep slopes, poor soils, areas of vegetation to be protected, etc. will fall in the same general locations, although what is suitable for one type of land use may be unsuitable for another. This is why it is important to have some idea of the program prior to completing the site analysis. The composite analysis map provides clear justification to the designer for where the most intensive development should occur on a site with the minimum environmental impact. It also highlights particularly positive elements of the site that should be accentuated in the subsequent design development. (See Fig.9)
The development of the program is the bridging step between the analysis and the synthesis or design phases. Kevin Lynch defines the program as composed of the four Ps population, package, performance, and patterns. Population refers to the actual user who may or may not be the client per se. Packaging involves the type and quantities of elements that will be provided in the design. Performance standards set the quality of elements expected, whether in terms of materials or function. Patterns refer to general physical relationships that should be achieved (Lynch 109).
As Simonds explains, in developing the program the designer responds to the clients initial statement of intent, modified on the basis of what he/she has learned at the end of the analysis phase. That is why there is no clear distinction between these steps in the design process. While the analysis is based upon a basic program concept, the potential of the site for development influences the planners ultimate program recommendations. The program should include:
a. A statement of goals that the project should achieve.In summary, the program is a guide for the designer to accomplish his/her task. It must be explicit enough to provide direction, but flexible enough to allow new ideas and directions to emerge as the design evolves. (Fig.10 illustrates the program resolved by Lilly and Loll as part of the design process for the Crooked Run Farm project).
b. A list of project objectives by which these goals will be accomplished.
c. A list of project elements that will be included and a description or analysis of their interrelationships.
CROOKED RUN FARM
To create diverse post mining land uses for Crooked Run Farm that will include farming, forestry, outdoor recreation, and wildlife habitat enhancement to improve economic development. The reclaimed site will serve as a model for multiple use areas on surface mined sites in the Appalachian region.
1. To revegetate areas previously disturbed by mining practices by introducing plant succession:
a. establishing forest communities of native species.2. To create viable aquatic and wetland environments:
b. utilizing plant densities that offer a compromise between timber production and wildlife habitat.
c. incorporating forest cover into areas of streamside management zones (SMZs).
a. establishing variety in water depth and soil saturation levels.3. To maximize farm production and increase herd capacity:
b. utilizing natural filters for adjacent farming activities.
c. developing habitats for wildlife.
a. developing areas that exhibit the best combination of site factors for cropland and pasture lands.4. To accommodate the public needs for diverse outdoor recreation opportunities:
b. meeting the demands of cattle production.
c. utilizing a gateless fencing concept.
a. incorporating facilities for extended stays.Program Elements
b. utilizing wildlife habitats for hunting and fishing activities when appropriate.
c. incorporating archery and firearms range facilities
d. adhering to barrier free design standards throughout the site.
|Hay Storage||Wildlife Forage|
|Wildlife Habitat||Recreational Trails|
|(Lilly and Loll 12-13)|
3. Synthesis (Design Phase)
a. Conceptual Design
The actual design manipulation begins at this point now that we have developed a program that delineates the project. Conceptual design begins with functional diagrams in which we explore the relationships of program elements and activities. This is first done as ideal or non-site related diagrams to establish the best abstract relationships among the various components of the project program. This is essentially a diagrammatic exploration in which the designer may move through a series of alternative arrangements until he/she achieves a solution which maximizes the positive relationships and minimizes the number of conflicts.
The resultant ideal functional diagram is then applied to the site, responding to the summary of the site analysis phase. As Lynch says, design consists of imagining patterns of activity, circulation, and physical form, as they will occur in some place (9). It is absolutely critical that the designer integrates the project facilities into the site, highlighting the positive character of the site, while protecting sensitive elements. Simonds echoes the significance of the design concept, which he refers to as the site-structure diagram from which the planning process becomes one of integration of proposed uses, structures, and site (123). Again, the designer explores a series of alternative arrangements, evaluating each in terms of suitability with natural site features, adjacent existing land uses and proposed development. The result is a series of site-related diagrams or concepts. (See Fig.11)
b. Preliminary Design
The conceptual plans are presented to the client to ensure his/her general acceptance of the basic program and design response. The selected concept is then refined into a preliminary design, resolving each program element into a physical component, suggesting basic form, size, and materials to be used. A design style appropriate to the site and clients needs or tastes is selected. This is presented to the client, user groups, and perhaps public entities by means of an overall plan and supplemental drawings to convey the proposed facility in a form understandable to the lay person. It also allows the designer to develop a preliminary cost estimate. Together, this provides sufficient information for those responsible to determine if the project is to go ahead, be abandoned or be revised, based upon the particular relevant selection criteria. (See Fig.12)
c. Site Plan / Master Plan
Presuming that the project is to go forward, the designer refines the development of the preliminary plan, giving precise form, dimension and indication of materials to the proposed elements. In other words, he/she precisely locates buildings and paved surfaces, delineates ground forms and planted areas, and indicates necessary utilities. The plan is frequently supplemented with a series of supporting drawings. These, which may include enlarged plan views of certain areas or components of a design, elevations and/or cross-sections of key elements, or three-dimensional views of the site design, are intended to clarify the clients understanding of the design. They show information that may be difficult to indicate in plan view such as vertical relationships, materials, and character of the proposed development. Together this information provides the basis by which a more precise estimate of the cost for the project can be determined. The site or master plan is submitted to the client for final approval. (See Fig. 13)
Supporting drawings indicating suggested views of areas from the master plan are shown in Figures 13a-e:
Figure 13a. Wetland habitat
Figure 13b. Aquatic habitat
Figure 13c. Upland habitat
Figure 13d. Skeet range, etc.
Figure 13e. Structure and furnishings
B. Design Implementation
Based upon the approved site plan or master plan, the designer is ready to begin the implementation phase of the design process. This is a series of drawings and written information referred to as the construction or contract documents. Together these will serve as the basis for contractors to prepare bids and for government officials to verify compliance with engineering standards and regulations. The actual construction documents required may vary on any given project, but generally will include: a layout plan, precisely locating structural elements to the site; a grading plan, establishing the relative elevations of program elements and the ground contour; a planting plan, locating and identifying all proposed vegetation; construction details and specifications, indicating materials, dimensions, and construction requirements of site furniture and structural elements.
The following examples that have been selected to
illustrate the implementation of the design process are being used with
permission of LUTHERCARE, the owner of the project and Derck & Edson
Associates, LLP, designers for the project. This project is the extension
of an existing retirement community. It will provide independent living
cottage units and assisted living units in a three-story structure as well as
related outdoor facilities. The overall plan for this phase of the
development may be seen on Fig. 14.
1. Layout Plan (See Fig.15) The layout plan is the drawing on which all of the structural elements of a proposed site development are accurately dimensioned and located such that they may be staked out on the site. Included in order of priority are:
4. Construction Details and Specifications (See Fig.18) Construction details and specifications are each a critical component of the design implementation package. The details specify the materials, dimensions, and construction techniques for the various design components of the site plan. Construction specifications are written directions of procedures and descriptions of the materials necessary to construct the elements of a site design project. They include detailed information relating to quality of materials, methods of measuring, mixing, safety requirements, etc. These are based on industrial and/or government standards. This information, along with the plan is legally binding for the contractor. Together, they provide a level of quality control for a project by indicating not only how a particular item is to be constructed but how it relates to adjoining items or materials as well. They also provide the basis for the contractor to develop an accurate cost estimate for a project.
After the awarding of a contract, the designer frequently has some form of supervisory capacity to clarify information provided and to ensure that construction proceeds in a timely fashion and to the standards specified. As indicated at the beginning of this section, some models of the design/planning process also include management/operation facets as part of the overall process. This suggests that the level of management available for the facility after construction be considered as the design developed. It also relates to post-occupancy evaluation in which the designer can benefit from observing how the site is used to evaluate the quality of the design and how well materials and relationships work "on the ground."
C. Professional Office Management and the Design Process
We have examined the design process in considerable detail in terms of theory. It might be instructive to now look at it briefly from the standpoint of the management of the professional design office. This may provide some insight as to its significance for actual site design application or implementation. Derck & Edson Associates, LLP have developed a model that we can look at as an example(See Fig. 19). We can see that their management framework really follows the design process as we have outlined it quite closely, delineating five primary phases:
I. Schematic Design, II. Design Development, III.
IV. Bidding Negotiations, and V. Construction.
Phase I encompasses two major components, pre-design and sketch plan activities. Pre-design includes activities such as initial client contact, preliminary program definition and basic site inventory and analysis. These are carried out simultaneously with contractual negotiation and staff assignments. Sketch planning covers use relationship studies with client and interdisciplinary consultant review. The end product of this phase is an agreement of the design scope and concept.
Phase II, Design Development, is where the design is essentially fleshed out. The landscape architect refines conceptual designs, integrating architectural building design with site design elements, including consideration of roads and utilities, layout, earthwork and grading, and environmental issues such as wetland or floodplain restrictions. The preliminary design is resolved to sufficient detail to evaluate costs, phasing, and other issues resulting from consultant and client review. Any conflicts or problems should be resolved through revisions, resulting in design acceptance and submission for approval by pertinent regulatory agencies.
Phase III, Construction Drawings, essentially involves preparation and development of the final layout, grading, and planting plans. These are supplemented with construction details and specifications.
Phases IV and V include the bidding process by which the contractors are selected and the actual construction takes place. The designer is involved to various degrees on different projects in supervision and approval as the project is built. There may or may not be post-construction evaluation as well.
It is interesting to see how the planning/design office can utilize this process in two distinct, but complementary ways. First of all, it allows the firm to propose land use development that is responsive to the clients needs as well as to environmental issues. At the same time, the design process provides an orderly sequence by which an office can organize its work force and administer the development of a project in a logical, organized, cost efficient manner.
D. Design Guidelines
As the conclusion to the previous section suggests, the design process does not really end. We are dealing with a living entity a work in progress involving natural, growing elements in the environment into which we are proposing to introduce man-made structural elements. This requires an understanding of how these potentially conflicting components may be integrated. We also are dealing with human clientele, both client and site users, who are subject to changing needs and attitudes. Assuming that the designed physical environment is a setting for some form of human behavior, the use of design guidelines may facilitate the opportunities for certain activities to take place. Consequently, the design might include a series of guidelines or standards to provide some direction to maintain the quality of the development as it matures or evolves over the life of the facility.
By nature, design guidelines are best provided as specifications of expected character or performance. The intention is to provide a desired character that may be continued with a minimum of restrictions. They consist of a diagram of land use, circulation, landscaping, patterns, rules, and illustrative details that will guide the form of future growth (Lynch 340).
Essentially such guidelines address particular issues that we might organize
under three categories:
1. Functional Suitability This may be stated very simply as concern that the form relates to the intended purpose. For example, pedestrian walkways are intended to facilitate foot traffic onto and around a site. Some of the physical form characteristics of concern are:- Widths minimum for anticipated volume and character of use.2. Compatibility of Form, Material, and Finish In the example of walkways, compatibility relates to appearance and function. The design guidelines will relate to how well the walks fit in:
- Slopes minimum limit for positive surface drainage; maximum desirable and acceptable limits for certain conditions.
- Surface Materials for climate, intensity of use, other conditions.- With the intended use or uses3. Durability This issue focuses on selection of materials and/or configuration appropriate for various criteria such as the climate, the intensity of use, or the maintenance capabilities.
- With the character of the setting historic, naturalistic, etc.
- With other design elements. E.g., of a particular architectural style or of certain materials or colors.
Ideally design guidelines are provided in the form of recommendations for a particular effect. On the other hand, rather than strictly advisory, they may provide the criteria for review and approval of a project. In composite on a given project they may significantly influence the physical form, character and density of the development. They are potentially very useful to the planner as references for the design of the next facility of a similar land use as well.